May 26 (Reuters) - Brisbane, Australia-based Tritium agreed to go public in the United States through a merger with a blank-check firm, valuing one of the world's largest electric vehicle charging-station makers at $1.2 billion, the company said on Wednesday.

The merger with Decarbonization Plus Acquisition Corp II

, a special purpose acquisition company (SPAC), will provide Tritium with gross proceeds of up to $403 million.

Unlike most SPAC mergers, the deal does not include raising a private placement or PIPE, adding to concerns that investors are no longer flocking to what was until recently one of Wall Street's hottest trends.

Investors worry that SPACs have taken many companies, often loss-making or even those without revenue, public at too-high valuations.

Founded in 2001, Tritium's customers include Ionity - the EV charging joint venture of Volkswagen AG , BMW

, Daimler AG , Ford Motor Co and Hyundai Motor Co - as well as Nissan Motor Co Ltd

, Honda Motor Co Ltd and Harley-Davidson Inc

.

Tritium started as a developer of technology for solar race cars and projects such as the management system for "Titanic" film director James Cameron's "Deepsea Challenger" submersible.

Cameron in 2012 used the submersible to complete the world's first solo dive to the deepest-known point on Earth, reaching the bottom of the Pacific Ocean's Mariana Trench.

Tritium, which has installed chargers in more than 40 countries, said the combined company will list its stock on the Nasdaq and trade under the ticker symbol "DCFC".

The coldest charging climate that Tritium has serviced is -35 degree Celsius, and the hottest charging climate of more that 50 degrees Celsius, according to its website.

(Reporting by Noor Zainab Hussain in Bengaluru; Editing by Shailesh Kuber)

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